June 2026 Monthly Summary for OfficeDev/teams-toolkit Key features delivered: - Open Plugin Specifications Import/Export Commands: Implemented the CLI commands atk import openplugin and atk export openplugin, enabling lossless interoperability with MOS3 projects. Added a TypeScript-based converter that accepts any Open Plugin Spec v1.0 (plugin/, claude-plugin/, cursor-plugin/) and scaffolds a complete TTK project with a v1.28 manifest containing agentSkills and agentConnectors. The converter and scaffolding are wired behind a feature flag and tested against a Contoso fixture across unit/integration/e2e tests (63 test cases). Major bugs fixed: - Resolved converter map parity issues for v1.28 by switching manifest handling to devPreview where appropriate, ensuring CreateAppPackageDriver validations pass. - Implemented security/robustness fixes in the importer/exporter path (path traversal guards, manifest read guards) and sanitized SKILL.md frontmatter to satisfy Teams Developer Portal validations. - Expanded test coverage from 52.77% to 100% for key openPlugin components and corrected ESLint/formatting across the module; ensured regression safety for the new import/export flow. Overall impact and accomplishments: - Enabled seamless interop between Open Plugin specs and MOS3-based Teams Toolkit projects, accelerating plugin development and deployment workflows. - Increased automation and reliability in project scaffolding, conversion, and packaging, reducing manual steps and onboarding time for plugin authors and partners. - Strengthened cross-team collaboration through clear change logs, tests, and documentation updates, contributing to a more maintainable and scalable integration layer. Technologies/skills demonstrated: - TypeScript-based converter, FxCore openPlugin module, generator/importer/exporter components, and CLI wiring behind feature flags. - Comprehensive testing strategy (unit/integration/e2e) with fixture-driven validation. - Template-driven scaffolding, manifest version handling (v1.28, devPreview), and code quality improvements (eslint formatting, tests, documentation).